The objective of this study is to determine the prevalance of peripheral arterial disease (PAD) in a defined population by non-invasive techniques, to investigate the etiology of peripheral arterial disease by evaluating the association of traditional cardiovascular disease risk factors with PAD, and to evaluate the degree of correlation between PAD and coronary heart disease (CHD) on a population basis in order to determine whether non-invasive tests of PAD can be utilized as a marker for CHD. A defined population from the local Lipid Research Clinic (NHLI study) is available. Half this population were selected as a random sample of the original total population and half were selected for hyperlipidemia. Existing data on diet, medications, alcohol use, cigarette smoking, past medical and surgical history including cardiovascular disease, family history, height and weight, blood pressure, arcus senilis, cholesterol, triglycerides, lipoproteins, and hematocrit will be updated, allowing unusual reliability of independent variables in analysis. Existing additional data on triceps skinfold, SMA-6 including uric acid and fasting glucose, clinical cardiac examinations, and resting and exercise electrocardiograms will be exploited. The dependent variable, PAD, will be measured by claudication history, traditional clinical examination, and newly developed non-invasive techniques. For the third objective, the PAD-CHD correlation, PAD measurements will be used as the independent variable and cardiac morbidity and/or mortality will become the dependent variable. Detailed validated mortality information will be available without cost from a continuing Lipid Research Clinic follow-up study.